Gale Crater

Gale Crater is a large crat3er on Mars that
is the landing and exploration site of NASA's Mars Curiosity rover. It has
a diameter of 14 kilometers (96 miles) and lies at coordinates 5.4°S ,137.8°E
in the northwestern part of the Aeolis quadrangle. At its center is a mountain,
called Mount Sharp, which rises about 5km (3 miles) from the crater floor
-- more than Mount Rainier rises above Seattle. Layering in the central
mountain suggests it is the surviving remnant of an extensive sequence of
deposits. Gale Crater has an area roughly equivalent to that of Connecticut
and Rhode Island combined. It is named for the Australian astronomer Walter
F. Gale.

The exposed layers on Mount Sharp tell a story about what Mars was like
in the past, perhaps spanning much of the history of the Red Planet. Studies
from orbit have revealed that the layers have different minerals depending
on their height. Near the bottom of the mountain are clay minerals, and
above these, layers with sulfur and oxygen-bearing minerals. Flowing water
appears to have carved channels in both the central mountain and the crater
wall. To get to Mount Sharp, Curiosity landed land in a flatter part of
the crater and is now slowly working its way upward, layer by layer. En
route, the rover will investigate how the layers formed and the environments
in which they formed.

Discovery of an ancient lake environment

A little more than a year after Curiosity began its investigations in Gale
Crater, scientists concluded that a lake once occupied the crater and that
this body of water would, over a period of millions of years, have been
capable of supporting primitive life of the type known as chemolithoautotrophs
– microorganism that break down the minerals in rocks as a source
of energy. On Earth, such lifeforms exist underground, in caves, and at
the bottom of the ocean.